The present invention relates to a decorative sheet used to make a decorative laminate and, more particularly, to a decorative sheet which is formed from a genuine vegetable parchment paper and which, when printed, provides a wood grain appearance to pressed wood articles when laminated to those articles. The present invention also relates to a method for making such a sheet.
Many household articles are made from pressed wood products. These products are formed by compressing wood particles and sawdust to form boards which are then used to manufacture articles such as furniture, counter tops, wall board, picture frames, cabinets and other similar articles. Because these products are not made from a single piece of wood, they do not have a wood grain appearance when they are formed. To provide these articles with a wood grain appearance, a printed, decorative sheet or foil is usually laminated to the board. The sheet usually carries a pattern, which simulates a wood grain pattern, to provide the pressed wood with the appearance of a real wood. These sheets are particularly useful because they can be used to simulate a variety of wood grain patterns thus reducing the need to use a variety of actual wood products and conserving wood.
When certain conventional decorative sheets become wet, liquid penetrates the sheet and comes into contact with the board to which the sheet has been applied. When liquid comes in contact with pressed board, the board swells and warps. Further, the sheet can ripple which destroys the illusion of the wood grain appearance and usually ruins the article. Although conventional foils and papers do provide a water barrier, they do not prevent the penetration of water which contacts the board for periods of time longer than a couple of hours. Thus, water remaining on the sheet for more than 3 to 4 hours may damage both the sheet and the underlying board.
Additionally, papers and foils currently used in the art to make decorative laminates have a tendency to curl once the wood grain pattern has been applied to the sheet. This curl makes it difficult to apply these papers and foils to the pressed wood to make an attractive laminate.
For these reasons, a need exists for a useful paper which can be used to create decorative sheets useful for making decorative laminates which, in turn, are made into household and office articles. A further need exists for a decorative sheet having an improved wet strength.